Galaxy’s gas molecules reveal its structure

Carbon monoxide seen flowing both toward and away from central black hole

GALAXY’S CORE This composite image from ALMA and the Hubble Space Telescope shows the distribution of gas (yellow and orange) and dust (blue) that form a spiral structure close to the supermassive black hole at the center of galaxy NGC 1433.

A surprising movement of molecules into and out of a galaxy’s core could be shaping its highly spiral structure.

Using ALMA, the Atacama Large Millimeter/submillimeter Array, astronomers led by Françoise Combes of the Observatoire de Paris zoomed in on NGC 1433, a galaxy that sits 32 million light-years from Earth in the Pendulum constellation. The researchers captured the most-detailed images to date of gas molecules moving around the galaxy’s central supermassive black hole.

The observations of carbon monoxide show the gas forming an unexpected spiral structure close to the center of the galaxy. They also identified a separate outflow of molecules moving away from core of the galaxy for about 150 light-years. The astronomers describe the new view of the galaxy October 16 in Astronomy & Astrophysics.

Such detailed observations help astronomers better understand how supermassive black holes in nearby galaxies consume matter and how that feeding influences the way the galaxies evolve.